The long term goal of this project is to understand the cellular and molecular mechanisms for loss of immunologic vigor with age and to promote immunorestoration. Present studies are focused on: (a) cellular etiology of immunosenescence, (b) the development of simple sensitive methods to assess the immunologic potential of peripheral blood cells, and (c) the development of immunorestorative methods. Unfortunately much of the work has been curtailed as a result of a Sendai parainfluenza outbreak in our aging animal facility.